I think six weeks will be up tomorrow. If I wanted to switch to Roon 1.8 Legacy, I would be doing so sooner rather than later. If I had a large local library and sketchy internet service or obsolete hardware I didn’t want to update/upgrade, I would probably switch to Roon 1.8 Legacy. You can switch back to Roon 2.0 at any time.
The answer is (unfortunately) no. The window to downgrade will be open for approximately 6 weeks from the release of Roon 2.0. During this time you can move back to 1.8 by following the instructions below.